The General Court of the European Union has rejected Microsoft's appeal of a 2008 European Commission antitrust ruling, but has reduced the fine Microsoft must pay from €899 million ($1.1 billion) to €860 million ($1.1 billion).

The European Commission had imposed the record-breaking fine because of Microsoft's failure to respect an earlier antitrust ruling that it disclose information about APIs used in its workgroup server products enabling competitors to develop interoperable products.

"The General Court essentially upholds the commission's decision imposing a periodic penalty payment on Microsoft for failing to allow its competitors access to interoperability information on reasonable terms," the court said in a statement.